颅内原发性淋巴瘤的MRI表现

颅内原发性淋巴瘤是较为少见一种恶性肿瘤,约占颅内全部脑瘤的0·8%~1·5%左右。影像学缺乏特征性表现,极易误诊为胶质瘤或转移瘤,笔者收集24例经手术和病理证实的颅内原发性淋巴瘤MRI影像资料进行回顾性分析,以提高对本病影像学认识。1材料与方法本组24例,男18例,女6例,年龄24~67岁,平均47·5岁。病程在3天~3个月不等。临床表现为:头痛、头晕、恶心、呕吐、言语不清、偏侧肢体障碍、意识模糊、精神异常等神经系统症状。所有病例均无免疫机能低下和中枢神经系统以外全身系统淋巴瘤。分别采用0·35T、1·0T的超导型MRI对24例脑内原发性淋…     

原发性颅内淋巴瘤的MRI表现

目的 :探讨原发性颅内淋巴瘤的MRI特征,以提高该病的诊断与鉴别诊断水平。方法 :回顾性分析15例经手术或立体定向病理活检证实的原发性颅内淋巴瘤MRI表现。结果:15例,共31个病灶,单发6例,多发9例(病灶1~4个),直径平均17.1 mm。幕上27个(大脑半球13个,丘脑8个,基底节6个),幕下4个,位于小脑半球。29个病灶T1WI、T_2WI及FLAIR呈等或等低均匀信号,DWI呈略高信号;增强扫描25个病灶呈团块状强化,6个呈环状或轻微强化。病灶周围均有脑水肿,其中重度23个,中度5个,轻度或无水肿3个。24个病灶邻近蛛网膜下腔,未见脑膜转移。幕下病例未见脑积水征象。所有病灶均未见坏死及囊变。结论:原发性颅内淋巴瘤具有特征性MRI表现:多位于幕上脑实质深部,多灶生长,邻近蛛网膜下腔、很少沿脑膜播散,多数病灶呈团块状强化,坏死囊变罕见,占位效应较轻,大部分病灶呈明显弥散受限。     

HIV 阴性的隐球菌性脑膜脑炎的 MRI 表现及临床意义

目的：评价磁共振成像(MRI)在人类免疫缺陷病毒(HIV)阴性的隐球菌性脑膜脑炎(CM)的表现及预后判断。方法回顾性分析2000—2013年于本院由脑脊液墨汁染色及脑脊液细菌培养确诊的19例 HIV 阴性的 CM 的 MRI 表现及临床预后,采用格拉斯哥结局评分量表进行预后判断：1分=死亡,2分=永久植物状态,3分=严重残疾,4分=中度残疾,5分=恢复良好。1~3分归为预后差,4~5分为预后良好。结果84.2%(16/19)的 MRI 检查异常,84.2%(16/19)表现为脑膜强化,31.6%(6/19)为脑肿胀,47.4%(9/19)为脑实质病变,5.2%(1/19)为血管炎。平均随访时间3.5年,9例 MRI 证实脑实质病变中5例(5/9,44.4%)出现预后不良。结论 HIV 阴性的 CM 的 MRI 表现多样,当出现脑实质病变可能提示预后不良。     

眼眶原发性淋巴瘤的MRI表现

目的：探讨眼眶原发性淋巴瘤的磁共振影像学表现,以提高其诊断的准确率。方法对11例经手术病理证实的原发性淋巴瘤的临床和影像学资料进行回顾性分析。结果眼眶原发性淋巴瘤的MRI特征如下：①好发于隔前眶周,以眼眶外上象限为主,包括眼睑、泪腺、结膜等;②无包膜,沿眼眶间隙蔓延塑形生长;③平扫T1WI呈等信号,T2WI呈稍高信号,增强呈中-重度强化;④DWI上表现为高信号;⑤边界较清晰,对周围组织结构侵犯、破坏少见;⑥囊变少见,出血、钙化罕见。结论眼眶原发性淋巴瘤MRI表现具有一定的特征性,MRI多方位成像可对肿瘤明确定位,并有助于定性诊断。     

颅内原发性中枢神经系统淋巴瘤的MRI表现

目的研究颅内原发性中枢神经系统淋巴瘤（PCNSL）的MR／表现特点。方法回顾性分析8例经手术病理证实的原发性中枢神经系统淋巴瘤的MR／表现。结果8例均为弥漫大B细胞型非霍奇金淋巴瘤。3例为单发,5例为多发,共13个病灶,其中大脑半球8个,基底节区4个,右侧背侧丘脑及基底节区1个。8例病变均表现为局灶性肿块,T1WI呈稍低或等信号;T2WI呈等或稍高信号。增强扫描7例呈明显均匀强化,1例轻度强化。6例瘤周重度水肿,2例瘤周中度水肿。结论原发性中枢神经系统淋巴瘤较为罕见,MRI是诊断该病的重要的无创性检查方法。颅内PCNSL影像学表现多样,但具有一定特征。     

椎管内原发性淋巴瘤的MRI表现

目的探讨MRI对椎管内原发性淋巴瘤诊断和鉴别诊断的价值。方法搜集经手术或穿刺病理证实的椎管内原发性淋巴瘤19例,行全身骨显像检查均未见确切骨转移征象,行骨髓穿刺检查均呈阴性,结合临床特征回顾性分析其MRI表现。结果 19例MRI表现为椎管内硬膜外软组织肿块,矢状面呈长条形,横断面呈半月形,14例向椎管外呈钻孔样生长。12例合并相邻椎骨骨质破坏,多位于椎弓附件区,其中8例软组织肿块范围大于骨质破坏范围,5例伴有压缩性骨折。软组织肿块信号均匀,边界清楚,以T1WI等信号、T2WI稍高信号为主,脂肪抑制序列呈高信号,增强后呈轻中度均匀或不均匀强化。骨质破坏为斑片状T1WI低信号,T2WI低或高信号,脂肪抑制序列呈高信号,结论椎管内原发性淋巴瘤MRI表现有一定的特征,把握这些特征有助于做出正确的诊断和鉴别诊断。     

艾滋病相关原发性中枢神经系统淋巴瘤的MRI表现分析

【摘要】目的：探讨获得性免疫缺陷综合征（AIDS）相关原发性中枢神经系统淋巴瘤 （PCNSL）的MRI表现。方法：回顾性分析11例经病理证实的AIDS相关PCNSL患者的临床及MRI资料。结果：11例AIDS相关PCNSL均为弥漫性大B细胞淋巴瘤,男10例,女1例,中位年龄49岁,CD4+T淋巴细胞计数中位数为39个/μL。共14个病灶,以幕上单发为主,主要分布于中线附近,其中单发病灶9例（81.8%）,多发病灶2例（18.2%）,位于幕上8例（72.7%）,幕下3例（27.3%）。T1WI为等低信号,T2WI信号高低不均,实性区以等低信号为主;T2 FLAIR大部分病灶周围见水肿,增强扫描病灶环形强化9个（64.3%）,团状强化3个（21.4%）,结节状强化2个（14.3%）,12个（85.7%）病灶出现不同程度坏死;DWI实性区高信号9个（64.3%）,等信号3个（21.4%）,低信号2个（14.3%）。结论：AIDS相关PCNSL的MRI表现具有一定特异性,仔细分析MRI各序列信号特征,结合临床表现、CD4+T淋巴细胞计数<50个/μL,有助于PCNSL的诊断。     

颅内畸胎瘤MRI表现分析

目的：探讨颅内畸胎瘤的MRI表现,以提高对本病的认识。方法：收集20例经手术和病理证实的畸胎瘤患者,对其MRI表现进行对照分析。结果：颅内畸胎瘤存在形式多种多样,其中囊性5例,囊实性3例,实性12例;中线及中线旁19例,非中线部位1例;合并出血2例,破裂3例,混合胶质瘤1例;术前误诊4例。找到脂肪成分是关键。结论：通过MRI多方位、多角度、多序列成像及增强扫描,大部分畸胎瘤具有特征性影像表现,可于术前作出定位及定性诊断。     

颅内淋巴瘤的MRI诊断

目的分析颅内淋巴瘤的MRI表现。方法回顾性分析23例颅内淋巴瘤的MRI影像学表现（其中15例手术治疗,5例伽玛刀治疗,3例未手术治疗直接行放、化疗）。男性16例,女性7例;年龄9～63岁,平均年龄36岁。23例均行MRI平扫,20例行增强后扫描（其中有17例行CT平扫）。结果颅内淋巴瘤具有以下特点①病灶单发或多发,以幕上为主;②类圆形或不规则形,T     

弓形体脑病的MRI表现

目的探讨弓形体脑病的MRI表现。方法本组病例20例。所有患者均接受了MRI及血清学免疫学(ELISA法)检查。5例行CT引导下的立体定向活检术。17例做了MRI增强扫描。15例进行了MRI复查。本组病例均进行了抗弓形体治疗。结果多数病灶位于大脑半球灰白质交界处(8例),其次为侧脑室周围(6例),病变多发为其特点(18例)。增强扫描绝大数病变呈不同程度强化(17例),其中以片状或斑片状强化最为常见(9例),其次为环形或半环形强化(7例)。血清学免疫学检查所有病例IgM或IgG抗体均呈阳性。所有病例抗弓形体治疗均有效。结论MRI对确定弓形体脑病的部位、范围及观察病灶演变情况、评价治疗效果有重要价值。     

Multiple intracranial hydatid cysts: MR findings

Multiple intracranial hydatid cysts are uncommon and usually localized in the supratentorial compartment. We report a case studied by CT and MR of multiple intracranial hydatid cysts scattered in various anatomic sites: supratentorial, infratentorial and also intraventricular. Correspondence to: J. M. Pumar Cebreiro     

MR findings of spontaneous intracranial hypotension

Purpose:
To present the MR features of spontaneous intracranial hypotension (SIH) and to discuss the correlation of MR features with clinical manifestations. Material and Methods:
Between 1997 and 2000, 15 patients with SIH underwent brain MR investigation. Lumbar puncture for the measurement of cerebrospinal fluid (CSF) pressure was performed in 6 patients. Follow-up MR was obtained in 8 patients after the clinical symptoms had improved. We analyzed the MR findings of SIH, and discuss them in relation to CSF pressure and clinical manifestations. Results:
Fourteen of the 15 patients with SIH had abnormal MR findings. The imaging findings included: diffuse pachymeningeal enhancement in 13 patients; descent of the brain in 6 patients; and subdural effusion/hematoma in 2 patients. Low CSF pressure was shown at lumbar puncture in 5 out of 6 patients. Follow-up MR examination in the symptoms-relieved status demonstrated a recovery of the abnormal MR findings in 6 of 8 patients. Conclusion:
Our data revealed that MR is sensitive in diagnosing SIH. The presence of characteristic clinical manifestations and MR features are virtually diagnostic for SIH syndrome. Invasive lumbar puncture is thus reserved for the equivocal cases.     

Spinal MR findings in spontaneous intracranial hypotension

Whole spine magnetic resonance (MR) imaging was used to evaluate the shape, size, signal intensity, and enhancement of the spinal spaces in a series of six patients with spontaneous intracranial hypotension (SIH). In all patients varying degrees of shrunken dural sacs, expanded extradural spaces with delayed homogeneous enhancement, and distended epidural venous plexuses were noted. In 83% (5/6) of patients, the MR signal of the expanded extradural space was similar to that of cerebrospinal fluid; 17% (1/6) showed an excessive fat deposit in the epidural space. Sixty-seven percent (4/6) of patients had a visible peridural membrane. After relief of the symptoms, one patient (1/4) showed persistence of the spinal abnormalities even though the brain abnormalities disappeared. In conclusion, the spinal MR findings of SIH, like its brain counterpart, are characteristic. In cases with clinical suspicion but without support from brain MR imaging, spinal MR imaging may be helpful in establishing the diagnosis.     

Spinal subarachnoid tumor seeding from intracranial metastasis: MR findings

We describe the magnetic resonance findings in two cases of spinal subarachnoid seeding from an intracranial metastatic lesion. Magnetic resonance imaging techniques using T1 and intermediate T1-T2 pulse sequences improve anatomical definition of the spinal cord-thecal sac and allow for optimal contrast to define metastatic deposits in the subarachnoid space. Heavily T2 weighted pulse sequences do not appear to be useful in the diagnosis of subarachnoid metastases.     

Esthesioneuroblastoma methods of intracranial extension: CT and MR imaging findings

Introduction

Esthesioneuroblastoma (ENB) is an aggressive neuroectodermal malignancy in the upper nasal cavity with local infiltration and lymphatic or hematogenous metastasis. The purpose of this paper is to document three types of direct intracranial extensions by ENB using computed tomography (CT) and magnetic resonance imaging (MRI).

Methods

Eleven patients with pathologically confirmed ENB were admitted in our hospital between December 2002 and December 2008. Their magnetic resonance (MR; n?=?10) and CT (n?=?8) images were retrospectively reviewed, and particular attention was paid to tumor location and extension, enhancement pattern, cervical lymph node metastasis, and Kadish stage.

Results

The majority of patients were male (8/11) with Kadish stage C tumor (10/11). Three types of direct intracranial extension by ENBs were put forward according to their MR and CT findings. The primary tumors were well-defined soft-tissue masses centered in the roof of the nasal cavity eroding into the paranasal sinuses (11/11), the contralateral nasal cavity (4/11), the cranial cavity (5/11), and the fossa orbitalis (3/11). The tumor parenchyma were hypointensity on T1-weighted images, heterogeneous hyperintensity on T2-weighted images, and isodensity or slight hyperdensity on CT images with scattered necroses (4/11) and marginal cysts(4/11). Their enhancements were significant and inhomogeneous. Cervical lymph nodes metastases were observed in four patients (4/11), but no pathologically proved distant metastasis was observed.

Conclusion

Three types of direct intracranial extensions by ENB can be found on CT and MRI: cranio-orbital-nasal-communicating ENB, cranio-nasal-communicating ENB, and orbital-nasal-communicating ENB.     

MR findings of an unusual intracranial neuroma simulating a meningioma

We report an unusual intracranial neuroma that simulated a meningioma on CT and magnetic resonance imaging. A diagnosis of meningioma was suggested because the tumor was tentorium-based; had enlarged into both the middle and posterior fossae; contained calcification and was homogeneous and densely enhancing on contrast CT; and was isointense with brain on T1- and T2-weighted images. The tumor proved to be a schwannoma with characteristic electron microscopic findings.     

Neurosyphilis in HIV carriers: MR findings in six patients.

Neurosyphilis, a sexually transmitted disease that can cause neurologic damage, has become increasingly prevalent in the AIDS era. HIV carriers can contract neurosyphilis without the presence of other concurrent opportunistic infections. Because MR findings of neurosyphilis are seldom reported, we retrospectively reviewed and evaluated contrast-enhanced MR images of six young (average age, 33 years) HIV-positive men with high serum and CSF VDRL titers indicative of neurosyphilis. All six patients tested negative for concurrent opportunistic infections. Five patients had acute or subacute strokelike symptoms involving the basal ganglia or middle cerebral arteries; one had a parietal convexity mass mimicking meningioma with headache and ataxia. Contrast-enhanced MR images showed patchy enhancement involving the basal ganglia and middle cerebral artery territories in the first five patients and the convexity mass in the sixth patient. On the basis of brain biopsy, a convexity mass was diagnosed in the patient with syphilitic gumma. The imaging findings of the remaining five patients represented ischemic infarct caused by meningovascular syphilis. After penicillin treatment, serum and CSF VDRL titers decreased, and neurologic signs and symptoms improved in all six patients. A follow-up MR study in the patient with the gumma showed that the lesion resolved almost completely. In young HIV patients with stroke symptoms or a convexity mass, neurosyphilis should be considered. Contrast-enhanced MR can reveal the extent of involvement by neurosyphilis and should be used to facilitate diagnosis and proper treatment.